Perhaps you should try some spelling variations:
"cong tinh trac snippets" » "cong trinh trac snippets", "cong vinh trac snippets", "cong thanh trac snippets", "cong sinh trac snippets", "cong tinh trang snippets", "cong tinh toan snippets"
"dung java java slippers" » "dung va java slippers", "dung java java slippery", "dung java java grippers"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("cong tinh trac snippets") or ("dung java java slippers"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cong tinh trac snippets") OR ("dung java java slippers"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cong tinh trac snippets ) or ( dung java java slippers ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cong tinh trac snippets") or ("dung java java slippers"))) or ("locating bug code snippets"))*.